Modules are a very important concept to separate different aspects in your application and for later re usage in other applications. Last but not least Modules will save compilation time as only the Module and not the complete project is being compiled.
Modules were introduce in Flex 2.01 Hotfix 2 and Moxie (Flex Builder 3 beta) also [...]

When you develop with AS3 and/or Flex 2/3 be sure to read the articles of Grant Skinner about
Flash Player 9 Garbage Collection and [...]

I was looking for a Flex component which acts like the iTunes view where you can browse through your covers.

Ely Greenfield made a wonderful component which exactly does it. He calls the component DisplayShelf and you find his blog post here with source [...]